In known sports timing systems the peripheral devices such as the starting pistol, starting gate or platform, photocell and arrival sensing means which provide electrical impulsions in response to the determining events, are coupled to a central processor which controls the operations as well as the processing of the information in each case through at least two conductive wires.
In the special case of swimming competitions to which the following detailed description will be limited the greatest difficulties seem to arise and the invention is revealed to its greatest advantage. Nevertheless, the invention may, without any particular difficulty, be adapted to other domains. In a swimming pool each swimming lane may be equipped with three peripheral devices, namely an arrival touch plate, a manual switch for duplicating the measurements by an official and a starting platform which moreover enables the determination of errors during relay races. For a swimming pool having ten lanes one may easily determine that a minimum of 31 conductive wires is necessary if it is acceptable to use one wire common to all devices and in most cases where such is not acceptable there will be a total of sixty wires.
The difficulties arising from such an arrangement are known . . . . The cabling is heavy and quite expensive, above all in the case of systems which are intended to be moved around from pool to pool. Moreover, numerous multipin connectors will be required and these are likewise expensive. Finally, all connections and connectors must be and remain watertight, this being furthermore an important element in the costs. The invention described in Swiss Pat. No. 572,250 which enables working with touch pads having contacts immersed in the water does not eliminate the necessity that all lines must be watertight after coming out of the electronics involved in such touch pads. In addition to their high price, known systems may thus have considerable and serious problems of reliability in view of the multiplicity of connectors and connections.